This invention relates to an analog-to-digital converter with all-parallel BiCMOSs(bipolar and CMOS transistors) that convert an image signal of a high speed analog signal to a digital signal.
An all parallel analog-to-digital converter has been mainly manufactured employing bipolar transistors. Recent tendency is to use CMOS transistors. An analog-to-digital converter only employing bipolar or CMOS transistors is seriously dependent on the characteristics of the individual elements. The bipolar transistors have good matching properties and high speed, but require larger current consumption and relatively larger dimensions compared to MOS transistors. For MOS transistors, their dimensions become smaller and smaller and processing speeds of them become faster. In addition, by the development of the process and circuit technology, the offset voltage difference has been reduced. The MOS transistors are, however, not adequate for the circuits that need the device matching high response and high speed.